Highly active and stable lanthanum-doped core-shell-structured Ni@SiO ₂ catalysts for the partial oxidation of methane to syngas

The nanostructures of silica-encapsulated NiO nanoparticles (NPs) doped with La, Ce, Ba, Co, Cu, and Fe were prepared and tested as catalysts for the partial oxidation of methane to syngas. Techniques that include TEM, XRD, Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), H ₂ temperature-programmed reduction (TPR), and O₂ temperature-programmed oxidation (TPO) were employed to characterize the fresh and used catalysts to understand the structure-performance relationship. The La-doped Ni@SiO₂ catalyst is superior to those doped with other elements. The effect of the reaction conditions on the catalyst performance over the best catalyst were also studied. The La₂O₃ species that were distributed uniformly throug